Upgrade to pantsbuild.pants 0.0.24.

There was 1 api break in BUILD files, repo no longer takes a
`push_db` file, but a `push_db_basedir`.

The rest is cleanups of deprecated aliases:
+ kill `pants()` wrappers
+ s/dependencies/target/
+ use `./pants goal test` in ci.sh for python tests

The pants-plugins/ needed no changes.

Testing Done:
CI went green here: https://travis-ci.org/twitter/commons/builds/36094495

Bugs closed: 325

Reviewed at https://rbcommons.com/s/twitter/r/1071/
Catch EnvironmentError in DiskMetricsWriter
Revert "Catch EnvironmentError in DiskMetricsWriter"

This reverts commit fe0b83c677b2d885623ac64caafe8461f9a1830f.

Accidental click in github UI.
Make globs('') match nothing at all.  This is consistent with rglobs and zglobs.  Include a few tests for globs(), including for this functionality.

Testing Done:
Ran glob tests (red/green/go)

Reviewed at https://rbcommons.com/s/twitter/r/1187/
Remove unecesary atexit handler and tests for module.
Merge pull request #332 from zmanji/fix-tunnel

Remove unnecessary atexit handler for tearing down ssh processes
Increment twitter.common to 0.3.2
Merge pull request #333 from zmanji/bump-version

Increment twitter.common to 0.3.2
twitter.commons: Release 0.6.0 of twitter.common.pants

Release twitter.common.pants 0.6.0 due to changed transitive deps.

Testing Done:
A functional noop; a test release was incorporated internally to unblock a release.

Reviewed at https://rbcommons.com/s/twitter/r/1329/
Fixing VarsJsonHandler and VarsHandlerTest for Java 7+ which changes hashmap iteration order

Testing Done:
Ran all java tests in commons with:

./pants goal test {src,tests}/java/com/twitter/common::
./pants goal test {src,tests}/scala/com/twitter/common::

under Java 7 and re-ran the java tests with Java 8

Reviewed at https://rbcommons.com/s/twitter/r/1368/